Selective drive mechanism



3 Sheets-Sheet l Mai'ch 1,4, 1939 R. J. BuRRovVs ET AL SELEGTIVE DRIVE MECHANISM original Filed Jan. 11, 193e March 14, 1939 R. J. EsuRRows ET AL SELECTIVE DRIVE MECHANISM original Fiied Jan. 11, 195e .s sheetssheet 2 R. J.BURRows TAL SELECTIVE 151mm MEGHANISM March 14, 1939.

original Filed Jani. 11, 193e s sheets-sheet 3 Patenten Mu. 14, 1939 PATENT loFFlcl?.

2,159,151 sELEc'nvE nnlvn MscnAN'IsM Robert J. Burrows, Battle' creek, .Imbert Lapsley,

Berrien Springs, and Alfred 0. Williams, Battle Creek, Mich., assignors to Clark Equipment Company, Buchanan,

l Michigan Orillll 58,712. Divided and.

Mich., a corporation oi al application 'January 11, 1936, Serial No. this application August 7,

.1931, lserial No. 157,856

13Claim8.

IZlhis invention relates to selective drive mechai nisms, and more particularly is directed to selective drive transmitting means for heavy road and rail vehicles such as trucks, busses, rail cars and the like.

The present application 'is a division of our co-pending application, Serial No. 58,712, filed January 11, 1936.

- Recent'developments in the design of trucks, busses and rail cars requiring relatively high speed operation with a considerable initial inertia load to be overcome in starting'the vehicle have introduced numerous problems such as the type of change speed drive transmission to be emp1oyed, 4and the selective control of this transmission for various torque requirements.

gear transmissions or the like.

It has been suggested, and some experimental I developmenthas been/attempted in connection l with high powered Diesel or semi-Diesel engines which are coupled with generators and electric driving motors, whereby thetrucks, busses or rail cars derive their `torque from their electrically driven motors. The resort to this construction has been due in a' large measure to the inilexibility of operation oi Diesel'engines, and the inability to accommodate such engines to change speed In addition, in

grder to Secure smooth starting -with gradual pick-up of the relatively heavy load and inertia due to the weight of the vehicle, the ordinary type of change speedgear transmission found in automotive vehicles does not appear to be adequate, especially when the ordinary type of friction type of clutch is employed. We have also found that,

. while electrical transmissions have excellent operating'characteristics and are reasonably reliable, the heavy weight and low 'eiliciency of the power transmission considerably offsets any advantages obtained by their use. A mechanical drive has Va much higher over-all einciencythan a combinaf tion of mechanical power units with electrical drive equipment. v

Other disadvantages arising from .prior types of/ combined-drive mechanisms of this class with which we are familiar are the 'increased s pacial requirements necessary for the conversionI umts and their control mechanism, and the increased number of separate rotating parts'which must be serviced, inspected and repaired, as well as the cost of the equipment.l

One'of the primary objects of the present inmvention isrvto provide a selective drive mechanism comprising Ychange speed gearing in which the gears for the various driving ratios remain constantly in mesh, and hydraulic clutches are em`- simplied and compact arrangement which may (Cl. Sli- 54) ployed for eilecting -ratio toanother.

-secured by such a drive resides in the exibility of operation, which may be obtained since no predetermined sequence of selection of the driving ratiosv is necessary. and such selection can s `be made from any one to any other ratio as determined .by the operator.

' s Another object of the present invention is to provide a.- common control means for simultaneously eiecting selection of the same driving ratio at a plurality of separately operating drive units, l this control means being positioned at any convenient or desired location in the vehicle being driven, or even in aseparate vehicle coupled to 15 the driving vehicle, such as an articulated bus or Vtrain design. I

In order to render the driving mechanism more ilexible in operatiomthe present -invention contemplates hydraulic clutches for selectively coupling the various sets of change speed gearing tothe driving shaft, irrespective of the speed at which the driving shaft is rotating. Thus the engine units may be brought up to substantially full speed operation prior to the coupling of the u driving gear mechanism thereto, and depending on the torque load and acceleration which is desired, any predetermined driving ratio may be selected and the load will be smoothly and gradually -picked up automatically by the hydraulic clutches, thereby' providing for smooth starting Iand acceleration of. the vehicle at any desired rate. l. Another feature of the presentinvention resides in a novel type of control mechanism for eilecting synchronized selection of the various driving ratios 'at each of the drive units, which mechanism is adapted to be extended to any desired number of drive units, all of which maybe simultaneously controlled from a single station or control point;

Another advantage secured by the present invention resides in the provision of a composite y driving gear assembly with vthe hydraulic clutches for operating the same being disposed entirely at one side of the various. sets of drive gears whereby thepressurelines for operating the hydraulic Aclutches are entirely clear and independent of of the gear mechanisms. Thislresults in a.y

be easilyassembled, and which is readily accessible for inspection and repair. .This also eliminates 'the necessity of' sliding clutches or the like in the transmission, whereby the axiall length of the unit can be reduced and the usual 55 shifter rods and actuating means therefor can be eliminated. Thus the selective transmission unit may be disposed at any desired portion of the vehicle, whereby the load distribution for the power unit and transmission can be adequately balanced in the vehicle body without regard to the necessity for torque mechanism connection thereto from the operators station. The remote control of this mechanism is of course effected through fluidpressure lines, which may manner.

We also provide for adapting a single selective drive mechanism to any desired drive ratio oy employing a set of interchangeable driving gears interposed between the driven shaft of the selective drive mechanism and the drive transmitting shaft leading to the axle.

We also provide for adapting a single drive mechanism to any desired drive ratio by employing a set of interchangeable driving gears interposed between the output shaft of the selective drive mechanism, and the drive transmitting means leading to the axle or other traction member.

Another advantage secured by the present invention is the provision of a mechanism for taking care of the change speed requirements at torque multiplications essential in such vehicle designs so that the clutching takes'place noise` lessly and efficiently, providing a transmission means from the prime mover to the axle that embodies all the advantageous operating characteristics and reliability of an electric drive without the attendant disadvantages of complicated control mechanism, low efficiency and heavy Weight. l

Another feature of the present invention resides in the provision of means for securing lubrication of the gears and bearings in the selective transmission unit, which is also under the control of an operator and is simultaneously actuated to provide a forced lubricant feed whenever the unit is in operation.

Other objects and advantages of the present invention will appear more fully from the detailed description which, taken in conjunction with accompanying drawings, will disclose to those skilled in the art the particular construction and operation of a preferred forni of the present invention.

In the drawings:

Figure l is a detailed sectional view through a preferred form of selective drive mechanism as embodied in the present invention;

Figure 2 is 'an end elevational view of the mechanisml shown in Figure l, together with a diagrammatic circuit embodying the controlling means therefor;

Figure 3 is a sectional view taken substantially of line 3--3 of Figure 1;

Figure 4 is a sectional view through one of the overrunning clutch mechanisms embodied in the present invention taken substantially on line l-fi og Figure l;

Figure 5 is a verticalsectional view through the hydraulic coupling member for introducing the iiuid under pressure' into the hydraulic clutches; and

Figure 6 is a sectional view taken on line 5 6 of Figure 1.

Considering now in detail the three-speed hydraulie transmission shown in Figure l, the driven shaft of a power unit is indicated at 8B and is provided with a ange 32 suitably secured amarsi by means of the bolts t3 to the end ange 65 of the enclosing rotatable casing indicated generallyv at 85 of the hydraulic coupling unit, which unit is supported at the end adjacent the engine unit by means of bearings 86, and at its opposite end is provided with a cylindrical recessed portion 81 adapted to have engagement with bearings 88, the casing B5 thereby being rotatably mounted to have conjoint rotation with the shaft 89 within the transmission housing and en-v be actuated electrically or in any other suitable' gine housing.

The front portion or end toward the power unit of the casing 85 is provided with a ring gear 96 having radially extending teeth adapted to be engaged by any suitable starting mechanism for initially starting the engine through the rotation of the shaft 8d. The hydraulic coupling casing $5 is provided with three rigid driving portions, indicated at 92, 93 and dil, each of which comprises a plurality of radially extending ribs or vanes formed integral with the various portions of the casing and forming centrifugal pump impellers, and having at their iree edges core ring portions 95 extending annularly v in integral engagement with each of the ribs of the driving elements 92, 93 and 9d.

The casing 85 is made up of a plurality'of component parts having radially extending flanges which are bolted together as indicated at dit, whereby the driving elements 92, 93 and S5 rotate as a unit upon rotation of the shaft 38. One of the intermediate elements @l is provided with an inwardly extending radial flanged portion 9B which separates two of the hydraulic clutches, while a second intermediate element 99 is also provided with a radially and angularly extending portion mi] separating the driving element S3 from the driving element Sli. The end element im carries the ribs of the third driving element 9B, and is mounted for rotation on the bearings 83,

Cooperating with each of the driving elements 92, Q3 and 9d is a corresponding driven element comprising turbine members M33, ylrl and M5, Each of the members H33, S and |05 is vprovided with radially extending vanes or ribsv It, corresponding to the vanes of the driving elements, and having an annular semi-cylindrical core ring member il disposed therein joining all of the ribs or vanes of each of these members and cooperating with the ring portion 95 of the driving element to provide a substantially closed annular core ring between the respective sets of ribs. 'The meinberl is provided with a hub portion m8 which is splined or otherwise nonrotatably secured to the splined end H39 of the shaft 8S. A suitable stop nut ll@ is threaded onto the reduced portion of the shaft 89 into engagement with the end face of the hub section NJB to prevent outward displacement of the member li with respect to the shaft 89. The extending reduced portion il? of the shaft 8B is piloted in the bearings lll carried by plate tl, whereby it is mounted concentrically with the drive shaft 8S.

The member Edil is provided with a hub portion H3, splined at il@ to a tubular sleeve member M5 loosely rotatable on the shaft B9. The member H3 is also provided with a cylindrical flange portion M6 whereby it is rotatably supported with respect to the shaft 89 by means of` the bearings l li engaging the shaft between the sleeve H5 and the hub portion |08 ofthe member tion of the tubularsleeve member ||5.

The member |05 is provided with a hub portion |20 which is splined or otherwise non- 4 rotatably secured to a sleeve member |22 freely rotatable upon the sleeve member ||5. The member |05 is mounted for rotation with respect to the exterior surface of the sleeve member ||5 by means of the roller bearings |23 carried between the extending cylindrical flange |24 formed integral with the hub portion of the member |05 and the outer surface of the sleeve ||5 intermediate the hubA portions ||3 and |20. A suitable lock-.nut |25 is threaded onto the end of the sleeve member |22 to prevent displacement of the hub portion |20 of the member |04 outwardly thereof.

It will be noted that the remote side of the hydraulic clutch casing 85 is supported on the bearings 88 which, about their inner bearing race, are supported upon the external surface of a cylindrical flange member |26 shown in more detail in Figures 3 and v5. 'I'he member |26 is provided with a radiallyextending ange |21 whereby the 'same may be bolted to a gear case housing |28 which houses the change speed gears employed in connection with the present transmission.' The bolts for securing the member |26 to the housing and in position about the external periphery of the sleeve I 22 are indicated at |29, and also serve to secure a retaining ring |30 in position for supporting the outer race of a ball bearing member |32 interposed between -the external surface of the tubularsleeve |22 and the retaining ring |30. g

The end of the sleeve member |22 ls provided with a radially extending portion |33 forming a ring gear having teeth |34, which teeth are adapted to mesh with the teeth |35 of a ring gear member |36 keyed or otherwise suitably secured to a countershaft |31 supported in suitable bearings |38 within the gear case housing |23. 'I'he opposite end of the shaft |31 is piloted in suitable bearings |39 carried in the retaining ring |40 which is piloted in the end of the housing |28, the ends of the countershaft 31 being provided with lock nuts |42 threaded thereon, the end of the shaft supported by the bearings |39 being suitably closed by `means of theciosure plate |43.

Suitable ball-bearing means |44 is interposed between the gear portion |33 of the tubular sleeve |22 and the external periphery of the sleeve ||5, whereby the two sleevss are mounted for relative rotationwith respect to each other. The ,sleeve ||5 is provided with a radially extending portion |45, having the radially extending gear teeth |46 formed thereon, and supported on .suitable double ballbearin'g means |41 for free rotation about the shaft 89.

The teeth ofthe gear portion of the sleeve ||5 are adapted to have engagement with the teeth y|48 oi' a gear member |49 which is mounted for free rotation about the countershaft |31 by means of the bearings |50 and |52.

frhe shaft as, extending through the hydraulicl clutch unit and through the gear housing |28, is piloted at its opposite end in the double-ballbearing means |53, being provided with -a suitable lock nut |54, the bearings |53 -being retained in position by the ring |55 pilotedin the end of the housing |28, the end of the shaft beingv enclosed by the cover plate member |56. The shaft 89 is also provided with an vintermediate splined portion |51 which is engaged by the splined hub |58 oi' a gear member |59 having rotation between the bearings |53 and a dor-ble set of bearings |60 and |62 which rotatably supporta gear member |63, having gear teeth |64, I

for free rotation about the shaft 89. The teeth |64 of the gear member |63 are adapted to mesh with the teeth |65 of agearfmember |66 which is splined at |61 to the countershaft |31, whereby rotation of the countershaft produces corresponding rotation of the gear |63 The teethI of the gear |59 are adapted to have driving engagement with the teeth of a gear member |68 splined at |69 to the tubular shaft portion |10 of a bevel gear member |12, .the shaft portion |10 of the gear member |12being` suitably supported in bearings |13 and |14 carried by `the. housing |15 which is bolted or otherwise secured to the upper surface of the housing |28,v as indicated at |16. While we. show a bevel gear |12 for transmitting torque from the selective drive unit to the driven axle, it ls obvious that in place of lthe gear |12 ashaft may be provided having means for coupling a torque transmitting member thereto such as a propeller shaft' -or the like, if the power unit is disposed in a manner such as to require such connection. Also, the housing |15 may be disposed in any angular position with respectto the shaft 89, and may be placed to the side of this shaft, as well as above I the shaft. This housing |15 may be termed an adapter housing, since it is within the scope of the present invention-to provide for any desired driving ratio by changing the gears |59 and |68, whereby the transmission/may be employed to produce various driving ratios between engine shaft and the bevel gear |12 independently of the individual gear ratios of the various speeds of the transmission. The bearings |13V are held in position by a pair of concentric retaining rings |11 andy |18 threaded into'a cylindrical boss portion |19 of the housing |15, the boss portion being provided with a closure plate |80 having a lug member .|82 for preventing relative rotation between the retaining rings |11 and |18 and the boss portion |19. A suitable set screw |83 is provided for retaining the outer race of thebearing |14 in position.

As has been pointed out, the gear member |49 is freely rotatable with respect to the countershaft 31. In order to provide for eiective rotation of the countershaft |31 upon predetermined rotation of the gear |49, we provide an overrunning clutch mechanism, shown more in detail in-Figure 4, comprising a ring element which is bolted to the side face of the gear |49 by means of a, plurality of bolts |86 which may be suitably ing member |90 is provided, at its inner portion, with a radially extending :flange having axially projecting'teeth |9| formed in theside face thereof, the teeth |9| being ofratchet formation A to engage with suitable ratchet teeth |92 formed in the side face of the gear |49 radially inwardly of the ring |85 and directly outwardly of the .bearing |52. The ratchet tooth engagement is shown in detail in Figure 6, from which it will be apparent that the clutch is free to rotate in one direction with respect to the gear |49, but rota tion in the opposite direction results in corre" sponding rotation of the gearv member. The

operation of this clutch will be described in de tail hereinafter.

The portion it@ of the clutch member i9@ is provided on its inner surface with helical splines |93 which are adapted to engage the helical splines i9@ of the shaft i3?.

A similar overrunning clutch arrangement is provided for clutching the gear i613 to the shaft Thus we provide the gear 63 with axially extending ratchet teeth N5 which are engaged by the teeth |96 of a clutch member Hdl', which clutch member is mounted 'in splined relation as indicated at 38 on the shaft te. The gear ISS carries a ring 99 bolted or otherwise suitably secured thereto, having the inwardly extending boss portions 20G carrying suitable ball members 2d? for engaging the tapered surface 283 of the anged portion of the clutch member itl. Thus the gear 63 can be directly clutched to the shaft SQ through the overrunning clutch mechanism described.

These overrunning clutches operate in a corresponding manner and a description of the operation of one clutch is therefore believed sufficient. The spring-pressed balls ldd have frictional engagement with the external surface of the hub' portion of clutch member igt. 'When gear M9 is rotating at a faster rate than shaft i3?, these balls act as lingers tending to drag the clutch member along in conjoint rotation therewith. This results in threading of clutch member i9@ along splines i 913 to move the member i9@ axially of shaft i3? to clutch the shaft With the gear E139. As long as gear id@ is in driving engagement the clutch will remain engaged, this engagement being assisted slightly by the tapered surface 985i of the hub of the clutch member, whereby a slight lateral component of the spring pressure of the balls 88 is exerted toward clutching engagement.

When the drive ratio is shifted so that shaft lS'i begins to rotate faster than gear M59, the ball members HB3 again act as frictional ngers, tending to slow down the rotation of clutch member i943. Due to the slanting rear faces of the ratchet teeth, member i9@ is initially moved outwardly to some extent, and the frictional drag results in further outward axial movement along splines ltd, resulting in complete disengagement of the member i850 from the gear M9. The operation of clutch member iil'i is similar.

Referring now in detail to the member 526, as shown in Figure 3, the ange l 2l is secured'to the housing 28 by means of a plurality of circumferentially spaced bolts i253. The flange is provided with a cylindrical extending portion ttt which is provided at oppositely spaced portions with a plurality of axially extending openings 2136 and 2li?. These openings are drilled from the extending end face of the cylindrical ange 'Zlib to a point adjacent the radial flange i121. Suitable parallel laterally extending passageways Z'llii and 209 are provided leading to the outer surface of the shoulder portion 2i@ of the member i245.

These openings extend into the enlarged passageways M2 and 293, shown in Figure 3, which project in opposite directions laterallyv to the outer portion of the housing 323, and there communicate with forwardly extending rectangularly shaped passagewaysgld and 2lb leading to suitardenti bolted or otherwise suitably secured tothe'hous ing 28 as indicated at 2id.

It will therefore be apparent thatliquid passing through the conduit 2 it will pass through the passageway 2id and the passageway 242 into the ports 2%, and thence will pass axially of the member i2@ along the passageways ft, being discharged axially outwardly of the passageways 2d@ at the' end of the cylindrical portion 205 thereof. Similarly, liquid passing through the conduit 2H and the passageways 2HE andk2l3 will enter the passageways 2m through the ports 2de, and will pass axially therethrough to the outwardly extending openings 2li? formed intermediate the ends thereof. The opposite ends of the passageway 2c? are closed by closure plugs 22@ which are retained in position by the split clamping ring 222 engaging in suitable slots formed in the lateral surface of the plugs 229. While the liquid must be under a slight pressure to insure its passage through these passageways, the operation of the transmission unit is in nowise-to be considered as a pressure operated system, since its operation is entirely controlled by centrifugal force, as Will be described hereinafter.

Referring now in detail to Figure 2, which shows diagrammatically the control mechanism employed for securing simultaneous shifting of any number of power units at the same time, We provide a-housing 1275 which is adapted to contain the hydraulic clutch element andV which may be formed integral `with the housing l28 containing the change speed gearing. The housings tt and 2'55, at their bottom surfaces, are provided with anged openings 276 to which may be bolted the flanges 2l? of coupling member 278 connected through the pipe 2id to a reservoir 28B, the pipe 279 having a similar coupling 282 at its opposite end bolted to an inlet opening in the reservoir 28d. Oil from the gear housings l2@ and 275 is thereby drained through the opening 2l@ and the pipe 219 into the reservoir 28e, and the reservoir is provided with a plurality of oil pumps indicated vdiagrammatically at 2%3, 353, Sd and 353,5.

The pump 233 is actuated by a suitable electric motor 235, which is connected by the conductor 2te to one power line 292, and by a conductor 268 to a contact segment 23S `adapted to be engaged by the controller switch member 29@ which is connected to the opposite conductor 28's' of a power line. The conductors 23? and 292 may be connected Ito any suitable source of electric current.

The pump 283 preferably comprises a plurality of individual oil pumps of the gear type, three of which are indicated at 2st, 392 and 2%. of the pumpsgl, 292 and 293 suppliesr oil to a corresponding nozzle 29d, 295 and 296 through conduits, 291, 29e and 299, respectively. These nozzles are directed at the points of meshing engagernent between the respective gears in the gear housing iZt, and the discharge of the nozzles may be varied to supply the proper amount of lubricating medium to each point of meshing engagement. Since all ofA the gears are constantly in mesh and rotate during operation of the system, it is essential that they be properly lubricated. For this purpose, instead of having the vgears run in oil, We provide for spraying oil or other similar lubricating medium upon the points of meshing engagement of the gears. This oil then drains from the gears and is conducted back to the reservoir 239 through the pipe 219, as previously described.

The reservoir 2186 is provided also with the three Each pump units 303, 304 and 305, which pump units have their outlets connected to the conduits 216,`

and 215, respectively, for passage through the passageways 206 and 201, respectively.

Each of the pump units 303, 304 and 305 is operated by an electric motor, as indicated at 301, 300 and 309. One terminal of each of the motors is connected through the conductors 310, 312 and .313 to the power conductor 281, while the other terminal of each of the motors is connected through the conductors 314, 315 and 316, respectively, to three corresponding separated contacts 311, 318 and 319, adapted to be selectively engaged by the control switch arm 290.

|)211e conduit 306 is adapted to supply oil through the coupling 320 to a conduit 322 extending through the interior of the housing 215 enclosing the hydraulic clutches, as shown in Figure 1, the conduit 322 being provided with one or more voutlet ports 323 directed into the circumferentially spaced openings 324 of the driving element .92 of the first hydraulic clutch.

For first speed operation, oil is forced by the pump 301, when Athe controller switch 290 has engaged the segment 289 and the contact 311 to actuate the motors 285 and 301, through the conduit 216 into the member 126, from whence this oil passes through the axially extending passageways 206 into the annular chamber indicated at 325 in Figure 1. From this annular chamber, the oil is adapted to pass through the angularly extending ports or passageways 326, spaced 'circumferentially in the hub portion 120 of the ele- 'ment 105, into the annular passageway 321 disposed .between the driving element 93 andthe driven element 104 of the intermediate hydraulic clutch. This oil entering the spaces between the,

ribs of the driving element 93 is forced outwardly past the annular rib 95 by the centrifugal force caused by rotation of the element 93, and is projected outwardly of the ribs of element 93 adjacent the outer peripheral edge thereof. The,

oil thus discharged from each of the parts formed by these ribs impinges on the adjacent surfaces of the ribs 106 of the driven element 104, and due to the circumferential component of velocity imparted to this oil by the rotation of element 93,

,produces an eective force on the surfaces of ribs 106 causing a rotative force to be applied to This force, multiplied by the moment arm corresponding to the arm radius of the element, produces a corresponding torque tending to rotate the sleeve 115.

'Ihe oil discharged by' rotation of the driving element 93 may thus be compared to an oil pressure developed by a centrifugal pump and discharged through nozzles against a hydraulic rotor or turbine member, namely, the driven element 104. The oil impinging on the surfaces of vanes 106 is forced inwardly by the. pressure of the oil behind it past the annular rib 101 and then across the inner surface of vanes 106' into contact with the ribs ofthe driving element 93, thus providing for rotary movement of this oil about the annular `ring formedby members and 101. At the same time the oil has a translational movement imparted to it in a circumferential direction bythe rotation of element 93 circumferentially, whereby the kinetic energy developed due to centrifugal force is imparted to the rotor 104 to produce rotation thereof. The

member 104 therefore has a tendency to come up to conjoint rotation with the member 93, although never actually reaching this point f due to the torque resistance thereon. Rotation of the mem- -ber 104 results in corresponding rotation oi the tubular sleeve 115, thereby producing rotation of the gear member 145, which drives the freely rotatable gear 149 in a counter-clockwise direction.

Inasmuch as the member 1'49 is free to rotate on theshaft 131, no rotation of the shaft 131 occurs until the clutch member |90 rides up the helical -splines 193 and 194, due to the relative l differential rotation between the member 149 and rotation of' theshaft 09 to rotate the gear 159" which, inturn, rotates the gear 168 to cause rotation of the bevelA driving gear 112. The rotation of the/bevel gear 112 results in 'rotation of either a vertically extending drive transmitting shaft leading to a drive truck under the vehicle, or of a suitably connected propeller shaft or the like, and thereby produces a driving torque for moving the vehicle. Thus rst speed operation of the transmission is produced.

When it is desired to shift fromrst to second I speeds, the operator or engineer merely moves the lever 290 from engagement with the contact 311 into engagement with the contact 318. This results in energizing the motor 308 to vdrive the pump 304, thereby producing ow of oil through conduit 211 into the port 215 of the housing 128. Oil then flows through the passageways 201 in the member 121, and is directed outwardly through the ports 219 into the annular space 328 between the members 94- and 105 of the right-hand hy;

draulic clutch member, as shown in Figure 1.

This oil is thrown outwardly by centrifugal force in the manner previously described and gradually fllls provided by the semi-circular elements 95401, causinga driving force to be transmitted to the member 105, whereby the member rotates the tubular sleeve 122, causing rotation of the gear 133. This results in driving engagement of this gear with the gear 136, causing positive rotation of the shaft 131 to which the gear 136 is splined. Rotation of this shaft is at a faster rate than the shaft was rotating during the driving engagement produced bythe clutch |90 due to rotation of gears 145 and 149, inasmuch as the gear ratio between the gears 133 and 130 is smaller than the ratio between the gears 145 and 149. This relative difference of rotation results in faster travel of bans sa with respect to ciutch 149 idles about the'shaft 131, and since no more oil from the pump is being forced into the intermediate hydraulic clutching elements, thesleeve merely idles about the shaft 89. The shaft 131,v directly driven under the influence of the the annular spaces about the ring driving engagement between thevgear 136 and the gear 133, rotates the gear 166 to produce rotation of the bevelgear |12 in thesame manner, but at a higher speed.

6 aieaii During this operation, oil from the intermediate hydraulic clutch member is being discharged through the peripheral ports 329 disposed outwardly of the vanes 93 and |06, this oil being displaced outwardly by reason of the centrifugal action produced by rotation of the casing 85. The area of the openings 329 with respect to the volunie of oil supplied is such as to allow building up of oil during the time that oil is supplied to the clutching element to allow the clutching of the driving and driven elements together, but discharges all of the oil by centrifugal force from the hydraulic clutch when the motor for supplying the oil to this clutch is deenergized. Thus the space within the vanes 93 and Hit is gradually emptied of oil by the centrifugal discharge of the oil outwardly of the casing through the ports 329. 'I'he relative rate of discharge of oil from ports 329 with respect to the rate at which oil is supplied for coupling engagement allows filling of the clutch in a predetermined relatively short period of time.

In order to prevent flooding of the selected clutch and possible leakage into an adjacent unenergized hydraulic clutch due to too much oil being supplied to the first clutch, suitable overflow means is provided in the radially extending flange S8 comprising a plurality of enlarged boss por-v tions 330'ormed therein and provided with radially extending passageways 332 opening outwardly of the casing 85, the passageways 332 being provided with ports 333 whereby as the level of oil lls up in the hydraulic clutch member until it reaches the ports 333, no displacement of oil except through ports 329 will take place, but as the oil level reaches the ports 333, oil will be .di'splaced outwardly ,through the passageways 332 to the external portion of the casing at a rate sufficient to prevent flooding of the clutch.

In a similar manner, metered displacement of oil from the hydraulic clutch elements Ql and |05 is provided through the passageways 331i, as shown in Figure 1, and suitable overilow means is provided in the depending wall portion |00 of the member 99 by means of the ports 335 and the radially extending passageways 33B formed therein.

Thus is will be apparent that the shift from first to seconddriving speeds of the selective change speed transmission can be accomplished simultaneously at all of the power units by the use of the hydraulic coupling element, the control being eiTected by movement of the switch handle 290 by the operator, whereby the energizing pumps for the lower speed are deenergized to provide for relatively slow declutching of the rst speed hydraulic clutch members by continued discharge of the remaining portion of oil through ports 329, and the pump units for the second or intermediate speed are simultaneously energized to provide for clutching of the second clutch elements. Inasmuch as the torque load imposed upon the transmission is a direct function of. the rate at which the elements will clutch, due to the fact that this torque is responsive for the re- V sistance to the kinetic energy of the centrifugally discharged oil between the relatively stationary A driven element and the rotating driving element as the oil is initially impinged against the rotor, it will be apparent that if one of the power units is taking more than its proportionate load of the car, it will not be clutched until such time as all of the units are taking their proportional load. This simultaneous self-compensating feature insures that each of the power units will take its proportionate part of the load during shifting oi the speedof the mechanism.

In order to shift from second to third speeds, the operator shifts the control lever 290 into contact with the contact SH3, thereby deenergizing the motor 308 and energizing the motor 309 for supplying oil tothe nozzles 323. This results in building up of kinetic energy in the oil passed into the hydraulic clutch comprising the driving element 92 and the driven element |86, thereby producing direct rotation of the shaft by means of the engagement of the hub portion IBB of the element M5 with the shaft ii. This thereiore produces a direct drive from the power unit to the shaft 8S, resulting in rotation of gears |59 and E58 to rotate the bevel driving gear |72. overflow means for the high speed hydraulic clutch comprises a plurality of bosses similar to the bosses but spaced therebetween and having corresponding ports opening into the annular space 332i disposed between the member 86 and the flange 98. Metered discharge outlets 339 areprovided for discharging a certain portion of oil from the hydraulic clutch during direct drive, as previously explained.

When the shaft 89 is directly driven by means of the driven element |05 coupled to the driving element 92, the relative rate of rotation of the shaft 89 is greater than the rate of rotation of the gear |63. Due to the frictional engagement of balls 202, the clutch member |91! is thereby backed away irom clutching engagement with the teeth |95 and produces idling movement of the gear |63 about the bearings |50 and |62 of the shaft 89. This results in idling of the gear |66 keyed to the shaft |31', and therefore results in only idling movement of the sleeves l5 and |22.

The

Without the provision of this overrunning type 'l of clutch, such as shown at and |91, the gears Woulddrive the rst and second speed elements at a high rate of speed during direct drive, since the gears are constantly maintained in mesh. It is therefore necessary to provide for some declutching means to prevent this operation of the intermediate speed gears during high speed operation of the car.

It is obvious that any number of such driving units may be simultaneously under thecontrol of the operator, and the switch handle 290 can be used for-controlling any desired number of driving units, since the conductors 3|0, 3I2, 3|3, 3| 4, 3 I 5 and 3 E may be provided with as many branch connections as desired, as shown in Figure 2, going to various other control motors for the operation of the other clutch elements of similar power units. Similarly, branch-conductors as shown at 340 are led from the conductors 286 and 288 to other constantly operating motors 285 connected to other of the power units, since it is essential that the motor 285 be energized at all times that any one of the speed control motors is energized, in order to provide for sufcient oil in the reservoir 280. Thus the segment 289 is so formed as to have contact engagement with the member 290 at all times that the member 290 is in. engagement with any one of the contacts 3l?, SIB, or 3I9. Similar branch conductors 342 are connected to the conductors for the respective terminals of motors 307, 308 and 309.

By the provision of the hydraulic clutching element which may be selectively controlled to provide for various speed ratios to the transmission, it is obvious that the operator can shift from rst Ato third speed, or from second to first to third speeds, or may shift his speeds in any desired a predetermined sequence of shifting' operations,

such as is common in the usual typeI of change speed transmissions.

We have provided forthe direct incorporation of a bearing and gear oiling system `ior the hydraulic transmission and gear casing. Inasmuch as the gears do not run in oil, it is necessary t provide some means for lubricating the various bearings in the assembly to prevent unnecessary wear and noise.

Thus we provide a suitable portion 34| in the cover plate |43 of the housing .|28 which is provided -with an' inwardly extending portion 342 piloted within an enlarged recessed opening 343 of the shaft |41. Oil is introduced through the port 34| from an oil pumpl unit 344 driven by the motor 285 and supplied through the conduit 346 into the recess 343 and this oil travels axially of the shaft through the passageway 341 extending therethrough. Between the bearings |50 and |52 we provide for a series of radially lextending vpassageways 348 whereby a portion of this oil is transmitted outwardly to the external surface of the shaft by centrifugal force, and is passed through suitable ports in the bearing separator member 349 to effect lubrication of the bearings |50 and |52. Thisalso provides for distribution of lubricating oil over the splines |94.

Adjacent the opposite end of the passageway 341 there is provided another series of radially extending ports 350 providing for lubrication 'of the bearing |38 through the diagonal passageways 352 in the gear member |36. The pilot bearings |39 at the outer end of the shaft |31 are lubricated by the passage of oil outwardly of the shaft along the Walls of the recess 343 into the annular space between the cover plate |43 and these bearings.

In a similar manner we provide a port 353 in the cover plate |56 of the housing 12a having communication with the recessed end 354 of the shaft 89. The shaft 89 isaprovided with a substantially axially vextending passageway 355 communicating with the recessed opening 354, this passageway receiving oil introduced into the port 353. The passageway 355 is provided with a first series of radially extending ports` 356 which communicate with suitable openings-351 in the hub portion of the gear |59 for effecting lubrication of the bearings |60 and |62. Y'A'second Vseries of radially extending passageways 358 -are provided adjacent the splined portion |98 of' the shaft for effecting lubrication of the ball bearings |41.

Additional series of radially 'extending passageways 359 and 360 are provided for lubricating the bearings |44 and |32, respectively, through suitable aligned openings in the sleeves and`|22.

At its remote end the passageway 355 is provided with an eccentrically extending passageway 362 communicating therewith, and extending inwardly to the piloted end I2 of the-shaft 89. The passageway 362 providesfor transmisl sion of oil from the passageway 355 to the pilot bearings lli.

Lubrication Yof the bearings 1, |23, and 88 is effected by the the various clutch units so that, by reason of the present system, all of the bearings of both the' hydraulic clutch assembly and the gear assembly are assured proper lubrication for reducing.

oilY employed for energization offer-able to actate either pump means.

' cylindrical column 366 extending centrally of the beveled gear shaft. 'I'he passageway 366 has suitable radially extending ports 361 adjacent the outer end thereof which communicate through the shaft and the bearing retaining nut |18 with the bearings |13 and supply lubrication oil thereto. A second series of radial passageways 368 are provided for supplying oil through the hub portion of the gear |68 to the bearings |14, the gear |68 having diagonal pasaeways therein directed vtoward the bearings The port 353 communicating with the passageway 355 of the main shaft 89 is supplied with oil from the unit 315 of the oil pump 283 through the conduit 316 communicating therewith. The oil for the port 364 is supplied by the unit 311 of the gear pump 283 through the conduit 318. .inasmuch as the motor 285 is constantly energized whenever the rail.car is in operation, it is apparent that lubricant will be forced to the nozzles 294, 295 and 296 and to the lubricating ports 34|.' 343, and 364 during all speeds of operation of the transmission, the pump 283 being a multiple gear type pump having a plurality of gears whichmay be arranged in a single gear Atrain to have their outlet ports connected to the various of the arrangements and modifications shown herein may be varied to a considerable extent, without, however, departing. from the underlying'principies forming the basis of the present invention. We therefore do not intend to be limited to the particular structure which weK have shown and described, except insofar as dened by the scope and spirit of the appended claims.

We claim: l

1. In combination, a clutch housing, a plurality of coaxially spaced hydraulic couplings therein, a sleeve member mounted coaxially thereof at 'one endiof said housing, said sleeve member having longitudinal passages therein, ports for certain of said passages opening into one of said couplings, ports for other'of said vpassages opening into another of said couplings.

let ports communicating with the interior of a,

second coupling, separate inlets for each set of passageways. fluid pump means individual to each inlet, and electrical means selectively op- 3. In combination, a plurality of axially spaced hydraulic couplings, a iiuid reservoir common to all said couplings, a corresponding plurality of fluid pumps in said reservoir, means operable for selectively actuating said pumps, conduits from each pump to the corresponding coupling, discharge means in each clutch periphery metered to discharge uid therefrom at a rate less than the corresponding pump delivers fiuidrthereto, and overflow means formed between adjacent couplings for limiting the quantity of uid therein during operation.

4. ln combination, a plurality of axially spaced hydraulic couplings, a uid reservoir common to all said couplings, a corresponding plurality oi iiuid pumps in said reservoir, means operable for selectively actuating said pumps, conduits from each pump to the corresponding coupling, discharge means in each couplingperiphery metered to discharge iiuid therefrom at a rate less than the corresponding pump delivers uid thereto, and overflow means formed between adjacent couplings for limiting the quantity of fluid therein during operation, said overow means having communication with said respective couplings at points spaced radially from the axis of rotation thereof.

5. A multiple hydraulic coupling unit comprising a rotatable coupling impeller housing, a shaft extending therethrough about which said housing is rotatable, a plurality of coupling lrotors in said housing, one of said rotors being keyed to said shaft, coaxial sleeves on said shaft having the other rotors successively keyed thereto, a bushing between the outer sleeve and the bearing support for one end of said housing, separate conduits extending through said bushing to .communicate with the interior of certain of said rotors, a separate conduit communicating with the interior of the shaft rotor, a fluid reservoir common to all couplings in said unit', means for selectively forcing uid under pressure through any one oi said conduits, and discharge means in said housing oremptying each of said couplings continuously at a rate less than that at which fluid is supplied through any one of said couplings.

6. In combination, a plurality of axially spaced hydraulic couplings having a common driving casing, a bushing extending into one end of said casing and having .two sets of longitudinally extending passa'geways, lateral inlet openings on opposite sides of said bushing each communicating with one set of passageways, means for selectively forcing uid under pressure. through said inlet openings, and means forming communicating ports between each set of passageways and one of said couplings.

7. In combination, in a. multiple hydraulic transmission unit, a shaft, a plurality of sleeves rotatable about said shaft, rotors keyed to each sleeve and to said shaft, a common driving casing enclosing all said rotors and rotatable independently thereof, fluid discharge means formed in the periphery of said casing adjacent each of said rotors, and means in said casing intermediate adjacent rotors for limiting the fluid in any one of said rotor units.

8. Means for coupling a powerunit to a driven member comprising a. plurality of hydraulic couarcaica pling means comprising driving elements constantly driven by said power unit and driven elements adapted to be selectively coupled with said driving elements, a housing, a pair of opposed ports in said housing, a radially anged cylindrical sleeve member between said housing and said coupling means, lateral passageways from said ports into opposite sides of said sleeve members, passageways extendingaxially of said sleeve member on opposite sides thereof, the passageways respectively communicating with different ones of said coupling means, and means for supplying fluid selectively to said ports to establish drive between the. driving and driven elements of one of said coupling means.

9. A multiple coupling unit including a hydraulic couplingcasing having a series of axially spaced driving coupling elements rotatable therewith, a driven shaft journalled in said casing, a plurality of driven coupling elements on said shaft respectively associated with said driving elements to form a series of uid couplings, only one of said driven elements being keyed to said shaft, an axially directed sleeve forming a journal support for one end of said casing, a plurality of working fiuid circuits, each circuit being formed by one of the respective driving and driven coupling elements, and means in said sleeve for selectively receiving and transmitting iluid to the circuits of certainof said couplings.

10. In combination, in a. hydraulic coupling unit, a drivingcasing? a pair of driven rotors axially spaced therein andindependently rotatable, said casing having a partition separating said rotors, one of said rotors having a hub journalled radially within said partition and provided With axial passages, a bushing forming a journal for the end of said casing and having its innerend closing said hub passages, means in said bushing forming separate fluid conduit paths, one of said paths having radial ports opening into the interior of said one rotor, the other of said paths having ports opening into said hub,

and means for selectively forcing iluid under pressure into each of said conduit paths.

11.A The combination of claim wherein said partition has means formed therein limiting the quantity of uid maintainable in the chamber formed by said one rotor, partition and casing.

l2. The combination of claim 10 wherein said hub passages open into the interior of said second rotor on the opposite side of said partition.

13. ln combination, a rotatable multiple hy draulic casing, a driven shaft rotatably supporting one end of said casing, a plurality of driven rotors spaced axially in said casing to form axially spaced couplings, one of said rotors being keyed to said shaft the other of said rotors being mounted respectively on coaxial sleeves extending about said shaft. aiiuid reservoir, a plurality of separate Working fluid circuits, each circuit being formed by oneof said couplings, a cylindrical bushing aboutsaid sleeves and rotatably supporting the other end of said casing, and means in said bushing for receiving uid from said reservoir and delivering it into certain of said uid circuits.

ROBERT J. BURROWS.

ALFRED O. WILLIAMS.

, -ROBERT LAPSLEY. 

